In order to facilitate their manufacture, aircraft are built in sections that are abutted to one another and transported to the assembly site.
Each section comprises a structural portion, a covering and a transmission circuit, both fluidic and energetic, such as an electrical circuit. The electrical circuit consists of different electrical harnesses, each equipped with several electrical cables.
When assembling two sections together, the electrical harnesses of a first section need to be connected to the electrical harnesses of a second section. For this purpose, it is known to use either a connection rack comprising a metal plate serving as a support for each of the harnesses and allowing connection of the two harnesses to each other, or electrical terminals equipped with studs on which lugs integral with the harnesses are mounted.
Safety standards require that at the level of the connection of two harnesses to each other, protection against the flow of water is provided, so as to prevent the flow of water on the connection between the two harnesses. A known protection adopts the form of an added metal sheet, welded or bolted to the metal plate used to support the harnesses.
Another standard requires that the connection plates provide additional connection spaces for connecting additional harnesses, for example to accommodate addition of a harness not initially planned.
Such an installation makes it possible to connect two harnesses together while complying with the various existing standards. It nevertheless suffers from a number of drawbacks.
Firstly, use of a metallic material weighs down the aircraft to the detriment of its fuel consumption. This increase in weight is not compensated for either by the additional spaces available, since they cannot in fact be used owing to the fact that they must remain free for possible connection of additional harnesses.
Secondly, installation of the protective sheet proves particularly difficult given the limited space in which the assembly operators can use their tools. Installation of the sheet is particularly difficult when the sheet is added by welding to the metal plate.
Finally, the design of each board is different depending on the maximum number of harnesses to be connected. Thus, a board is sometimes redesigned because too few connection positions have been planned in relation to the number of harnesses to be connected.